Default modality is abstract for interface. REDUNDANT_MODIFIER_FOR_TARGET applicability reduced #KT-12302 Fixed

compiler/frontend/src/org/jetbrains/kotlin/resolve/ModifiersChecker.kt

@@ -93,9 +93,7 @@ object ModifierCheckerCore {
 
     // NOTE: redundant targets must be possible!
     private val redundantTargetMap = mapOf<KtModifierKeywordToken, Set<KotlinTarget>>(
-            ABSTRACT_KEYWORD  to EnumSet.of(INTERFACE),
+            OPEN_KEYWORD  to EnumSet.of(INTERFACE)
-            OPEN_KEYWORD      to EnumSet.of(INTERFACE),
-            FINAL_KEYWORD     to EnumSet.of(ENUM_CLASS, OBJECT)
     )
 
     val possibleParentTargetMap = mapOf<KtModifierKeywordToken, Set<KotlinTarget>>(

compiler/testData/diagnostics/tests/declarationChecks/illegalModifiersOnClass.kt

@@ -6,13 +6,13 @@
     <!WRONG_MODIFIER_TARGET!>override<!> companion object {}
     <!WRONG_MODIFIER_TARGET!>open<!> companion object {}
     <!WRONG_MODIFIER_TARGET!>abstract<!> companion object {}
-    <!REDUNDANT_MODIFIER_FOR_TARGET!>final<!> companion object {}
+    final companion object {}
 }
 
 <!WRONG_MODIFIER_TARGET!>override<!> object B1 {}
 <!WRONG_MODIFIER_TARGET!>open<!> object B2 {}
 <!WRONG_MODIFIER_TARGET!>abstract<!> object B3 {}
-<!REDUNDANT_MODIFIER_FOR_TARGET!>final<!> object B4 {}
+final object B4 {}
 
 <!WRONG_MODIFIER_TARGET!>override<!> enum class C {}
 <!WRONG_MODIFIER_TARGET!>override<!> interface D {}

compiler/testData/diagnostics/tests/modifiers/redundantTargets.kt

@@ -1,10 +1,10 @@
 <!REDUNDANT_MODIFIER_FOR_TARGET!>open<!> interface First
-
+// Now inspection
-<!REDUNDANT_MODIFIER_FOR_TARGET!>abstract<!> interface Second
+abstract interface Second
-
+// Now inspection
-<!REDUNDANT_MODIFIER_FOR_TARGET!>final<!> enum class Third {
+final enum class Third {
     FOURTH, 
     FIFTH
 }
-
+// Now inspection
-<!REDUNDANT_MODIFIER_FOR_TARGET!>final<!> object Sixth
+final object Sixth

idea/idea-core/src/org/jetbrains/kotlin/idea/core/psiModificationUtils.kt

@@ -229,7 +229,10 @@ fun KtModifierListOwner.canBeProtected(): Boolean {
 }
 
 fun KtDeclaration.implicitModality(): KtModifierKeywordToken {
-    if (this is KtClassOrObject) return KtTokens.FINAL_KEYWORD
+    if (this is KtClassOrObject) {
+        if (this is KtClass && this.isInterface()) return KtTokens.ABSTRACT_KEYWORD
+        return KtTokens.FINAL_KEYWORD
+    }
     val klass = containingClassOrObject ?: return KtTokens.FINAL_KEYWORD
     if (hasModifier(KtTokens.OVERRIDE_KEYWORD)) {
         if (klass.hasModifier(KtTokens.ABSTRACT_KEYWORD) ||

idea/testData/inspections/redundantModalityModifier/inspectionData/expected.xml

@@ -87,4 +87,20 @@
         <problem_class severity="WARNING" attribute_key="NOT_USED_ELEMENT_ATTRIBUTES">Redundant modality modifier</problem_class>
         <description>Redundant modality modifier</description>
     </problem>
+    <problem>
+        <file>redundantModalityModifier.kt</file>
+        <line>56</line>
+        <module>light_idea_test_case</module>
+        <entry_point TYPE="file" FQNAME="temp:///src/redundantModalityModifier.kt" />
+        <problem_class severity="WARNING" attribute_key="NOT_USED_ELEMENT_ATTRIBUTES">Redundant modality modifier</problem_class>
+        <description>Redundant modality modifier</description>
+    </problem>
+    <problem>
+        <file>redundantModalityModifier.kt</file>
+        <line>58</line>
+        <module>light_idea_test_case</module>
+        <entry_point TYPE="file" FQNAME="temp:///src/redundantModalityModifier.kt" />
+        <problem_class severity="WARNING" attribute_key="NOT_USED_ELEMENT_ATTRIBUTES">Redundant modality modifier</problem_class>
+        <description>Redundant modality modifier</description>
+    </problem>
 </problems>

idea/testData/inspections/redundantModalityModifier/redundantModalityModifier.kt

@@ -52,3 +52,9 @@ abstract class AbstractDerived2 : Interface {
     // Redundant
     override open val gav = 13
 }
+// Redundant abstract interface
+abstract interface AbstractInterface
+// Redundant final object
+final object FinalObject
+// Open interface
+open interface OpenInterface